n = int(input())

d = set()

for i in range(n):
    com = input().split()
    if com[0] == "insert":
        d.add(com[1])
    else:
        print("yes" if com[1] in d else "no") n = int(input()) n int(input()) int input() input d = set() d set() set for i in range(n):
    com = input().split()
    if com[0] == "insert":
        d.add(com[1])
    else:
        print("yes" if com[1] in d else "no") i range(n) range n com = input().split() com input().split() ().split () input split if com[0] == "insert":
        d.add(com[1])
    else:
        print("yes" if com[1] in d else "no") com[0] == "insert" com[0] com 0 "insert" d.add(com[1]) d.add d add com[1] com 1 print("yes" if com[1] in d else "no") print "yes" if com[1] in d else "no" com[1] in d com[1] com 1 d "yes" "no" n = int(input()) int(input()) n com = input().split() input().split() com d = set() set() d
n = int(input())

d = set()

for i in range(n):
    com = input().split()
    if com[0] == "insert":
        d.add(com[1])
    else:
        print("yes" if com[1] in d else "no")
